A giant nebula in M33 ... NGC604 is over 40 times the size of the visible portion of the Orion Nebula. It is over 6300 times more luminous than the Orion Nebula, and if it were at the same distance it would outshine Venus.
Holy Cow Leo you are really going for it on this one. That's amazing as a concept to be imaging a distant major galaxy's nebula and get a good result like that.